The invention relates generally to ground working equipment, such as agricultural equipment, and more specifically, to a down pressure control system for an agricultural implement.
Generally, fertilizer application implements are towed behind a tractor or other work vehicle via a hitch assembly secured to a rigid frame of the implement. Certain fertilizer application implements include a storage tank configured to hold fluid fertilizer, and to provide the fluid fertilizer to injection nozzles. The storage tank is supported by a frame, which may also support a toolbar assembly having openers and the injection nozzles (e.g., as elements of respective row units mounted to the toolbar assembly). The openers form a path for fertilizer deposition into the soil. Specifically, the openers are used to break the soil, thereby enabling the injection nozzles (e.g., positioned behind the openers) to deposit fertilizer at a desired depth beneath the soil surface. In certain embodiments, the implement may include knives (e.g., positioned behind the openers), instead of the injection nozzles, to flow the liquid fertilizer into respective trenches formed by the openers and the knives. Using such implements, fertilizer may be distributed throughout a field, either before or after planting, to facilitate enhanced crop development. Unfortunately, the openers may over-penetrate or under-penetrate the soil because of variations in soil density, terrain slope, and weight distribution across the toolbar assembly. Under-penetration or over-penetration may cause fertilizer to be deposited at an undesirable depth, thereby reducing fertilizer efficiency.